Bladder Snail Size Differences Between Tanks

[jwcarlson]

I'll preface this by saying that I don't have pictures right now.  But I can get some later.  I've never noticed a large difference in bladder snail sizes until I started using RO water to cut my tap drastically and lower the pH.  My standard tap water is 8.2 pH, GH and KH are something like ~20 degrees each.  All of my fish have lived in this water as well as the snails I have.  When I started setting up apisto tanks, the snails went from maxing out in size at MAYBE 1/4" and being pretty markedly 'bigger' at that size compared to the others in the tank.  Like "oh, that's a pretty big one!"

Now, in my apisto tanks it's not uncommon AT ALL to see a bladder snail at 3/8" and I'd bet there are a couple even bigger than that.  They are HUGE compared to the "big ones" in my standard tap water tanks.  Apisto water is around 7.4 pH, KH of ~2, GH ~4.  77 degrees, but community tanks and CPDs are 75.  Discus is 85.

Has anyone noticed this difference?  I initially thought maybe it was predation of larger snails, not nothing really kills them in my discus tank or in the community tank with a bunch of tetras and corys.  This size difference also occurs in my QT and CPD tanks where it's straight normal tap water and in the QT tank, no fish at all most of the time.  I also use it to hold plants and when I QT fish I usually take all the plants out and put them in a bucket (including any snails in the tank).  Then when QT is done they end up back in there.

They also appear to grow faster and die sooner?  Or at least I notice death more in the apisto tanks.  (seeing the empty shells).  Are their shells maybe thinner from less calcium and so they grow bigger/faster?  I'll try to get a side-by-side with a "big" one from QT or CPD tank and a big one from the Apisto tank.  

Edited April 10, 2023 by jwcarlson

[Guppysnail]

It’s funny you mention this. I just noticed the exact same thing. I’ve only had my Apisto for a few weeks and also cut their water with RO. I have similar tap to yours. The big difference I notice is the Apisto are …not efficient… at eating. I think more floats past them than they catch. They also are not doing a stellar job at cleaning up the leftovers. 
I put a new piece of spider wood in 2 days ago and it looked like Christmas lights with my gold bladder snails and they were unusually large. I was wondering if it was the excess food laying about that does not exist in my other tanks. 

[jwcarlson]

My apisto tanks are certainly overfed... mostly BBS and they wait until they mostly sink and then eat them off the bottom.  So I'm sure they're missing a lot of it.  Also lots of newish plants that melted and plenty of algae.  My discus tank has TONS of food dumped in, but I'm also changing 90% of water daily, so it doesn't necessarily sit around quite that long?

Perhaps it is just maximum snail nutrition.  Maybe I should start breeding monster bladder snails and ditch trying to get a successful apisto spawn? 😄

Me after selectively breeding my "jumbo bladder snails" for a year:

[jwcarlson]

The smaller one would be pretty big for my other tanks.  The bigger one is a pretty standard adult from my apisto tanks. 

[nabokovfan87]

On 4/10/2023 at 8:46 AM, jwcarlson said:

They also appear to grow faster and die sooner?

Metabolism is very likely due to the temperature. It'd be interesting to see the size average, lifespan, and temp for each situation.

Second to that variable above is going to be how much food, how often, and can the snails grow enough shell to keep up.

On 4/10/2023 at 8:46 AM, jwcarlson said:

I initially thought maybe it was predation of larger snails, not nothing really kills them in my discus tank or in the community tank with a bunch of tetras and corys. 

Definitely interesting.

[Lennie]

Interesting. I've had bladder snails in my 29g too, before they are outcompeted by MTS. They were pretty small as well. I also have similar water parameters to you with high ph. 

 

[jwcarlson]

@nabokovfan87

I could see that being the case regarding temp.  Size would be hard to convince me that 77 in apistos is different enough from 75 in the community tank.  

I did see some research showing clutch size and lifespan is very different at different temps which makes sense (higher temp = shorter life, reproductive span, and smaller clutches).  

I'll see if I can find that again. 

[jwcarlson]

This study:

Effect of controlled temperatures on gametogenesis in the gastropods Physa acuta (Physidae) and Bulinus tropicus (Planorbidae) | Request PDF (researchgate.net)

Summarized here:

Bladder Snail – Detailed Guide: Care, Diet, and Breeding - Shrimp and Snail Breeder (aquariumbreeder.com)

With the following table:

 

 

[Odd Duck]

I’ve had a conversation with @modified lung about culturing Daphnia and Ceriodaphnia and he mentioned that he thinks fresh dechlorinators can inhibit their growth or reproduction (I can’t remember now which it was or if it was more just in general success or failure of the colony).  He suggested that I use either old tank water or remineralized RO. I wonder if that could be a factor - using RO and less dechlorinator in the tap portion of the mix.  Maybe he has some thoughts and can chime in on this?  After following his advice, my Daphnia are finally succeeding and actually breeding for the first time and Ceriodaphnia are doing well, also.